| 摘要 |
<p>PURPOSE:To provide an electrically reloadable EPROM specially meeting a low voltage power supply specification. CONSTITUTION:A portion between a semiconductor substrate 8 and floating gate electrode 1 is formed with a thin tunnel oxide film 2, gently sloped N type diffusion layer 5 is provided at the drain side, moreover, a DSA construction comprising a N type diffusion layer 6 and P type diffusion layer 7 at the source side is provided, and its source side diffusion layer has a construction having several bits to several ten bits of connected EPROM cells. When reloading the data, writing is performed by hot electron implantation for all bits and channels, thereafter, a proper potential is given to each word line and digit line, by which the threshold voltage after erasing required EPROM cells can be made higher than 0V at least and be lowered to the level with which low voltage operation is possible without dispersion of each bit.</p> |
